Nanotechnology in a Nutshell Christian Ngô • Marcel Van De Voorde

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Nanotechnology in a Nutshell Christian Ngô • Marcel Van de Voorde

Nanotechnology in a Nutshell

From Simple to Complex Systems Christian Ngô Marcel Van de Voorde Edmonium Faculty of Applied Sciences Saint-Rémy-lès-Chevreuse DELFT University of Technology France The Netherlands

Image Courtesy H. DAWSON, Ch. ABERG, M. MONOPOLI, University College Dublin (Ireland). The picture on the cover page of the book represent: Nanoparticle protein corona engaging with a cellular receptor.

ISBN 978-94-6239-011-9 ISBN 978-94-6239-012-6 (eBook) DOI 10.2991/978-94-6239-012-6

Library of Congress Control Number: 2013953213

Ó Atlantis Press and the authors 2014 This book, or any parts thereof, may not be reproduced for commercial purposes in any form or by any means, electronic or mechanical, including photocopying, recording or any information storage and retrieval system known or to be invented, without prior permission from the Publisher.

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Springer is part of Springer Science+Business Media (www.springer.com) Foreword

Science and technology are engines of progress in society. They are also of increasing interest to the general public, consumers, and policy makers, in addition to scientists and economists. New ground for science policy was broken in January 2000, when the then President Clinton announced the National Nanotechnology Initiative driven by a 20-year vision. Nanotechnology currently is well recognized as a science and technology megatrend for the beginning of the twenty-first century. This book aims to show where nanotechnology is now––transitioning to complex systems and fundamentally new products—and communicates the societal promise of nanotechnology to specialists and the public. All materials we see around us have a nanostructure that determines their behavior. Because of nanotechnology—control of matter at the atomic, molecular, and macromolecular levels where specific phenomena enable novel applications— major industries and medicine are changing. Advances at the nanoscale are leading to new understanding of nature and manmade things, and an increased ability to restructure matter at the atomic and molecular levels. The multidisciplinary field of nanotechnology has been expanding since 2000 in large public and private programs around the world, reaching an annual global investment in 2012 of approximately $20 billion. Most of what has already made it into the marketplace is in the form of ‘‘First Generation’’ products (passive nanostructures with steady behavior, such as coatings, nanoparticles, nanowires, and bulk nanostructured materials). Many small and large companies have ‘‘Second Generation’’ products (active nanostructures with changing behavior during use, illustrated by transistors, amplifiers, targeted drugs and chemicals, sensors, actuators, and adaptive structures) and embryonic ‘‘Third Generation’’ products (nanosystems, including three-dimensional nanosystems using various synthesis and assembling techniques such as bio-assembling; nanoscale robotics; networking at the nanoscale and multiscale architectures; after 2010) in the pipeline. Concepts for ‘‘Fourth Generation’’ products, including heterogeneous molecular nanosystems, are only in research. Each generation of new products is expected to include, at least partially as components, products from previous generation. The labor and markets are estimated to double every 3 years, reaching a $3 trillion market encompassing 6 million jobs by 2020 if one assumes that the rates of increase in the last 12 years would continue. Nanotechnology has the promise to create a basic understanding and a general purpose technology with

v vi Foreword mass and sustainable use by 2020 (‘‘Nanotechnology Research Directions for Societal Needs in 2020’’, Springer, 2011, www.wtec.org/nano2/). While expectations from nanotechnology may have been overestimated in the short term, the long-term implications on health care, productivity, and the environment appear to be underestimated. This volume will stimulate further interest and bring faster societal recognition to nanotechnology and overall to emerging technologies.

Mihail C. Roco Senior Advisor for Nanotechnology National Science Foundation Arlington USA

Reference

M. C. Roco, C. A. Mirkin, and M. C. Hersam, ‘‘Nanotechnology research and directions for societal needs in 2020’’, Springer, 2011 Presentation of the Book

It is rare for a new technology to transform all aspects of human activity. In history, one can identify agriculture, the industrial revolution, and the advent of personal computing as truly unprecedented advances. In the twenty-ﬁrst century, nanotechnology is predicted to provide the next revolution. Nanotechnology spans all of our human activity, from agriculture, medicine and food to clothing, from transport to industrial processes. It is not just about the ability to understand and manipulate material at the nanoscale, it is the way in which a new technology will be used to change the way products are made and to provide a step change in the functionality that they provide. Nanotechnology has been a part of many commonplace products for hundreds of years. Steel, concrete, adhesives, and cosmetics have all used nanoscale mechanisms to achieve their properties, but developments have historically been through craft skills and trial-and-error rather than through science and engineering. Recent developments in experimental techniques that allow the study and manipulation of materials at the nanoscale, coupled with novel manufacturing techniques, mean that we are poised to be able to realize new properties and functions that previously could not be achieved. One nanometer (nm) is one millionth of a millimeter (mm) or/and a billionth of a meter. As a matter of comparison, ants range in size from 2 to 25 mm and a red blood cell has a size around 6,000–8,000 nm. Ultimately, all living and inert matter is made of atoms, which have a dimension well below the nanometer range, typically a diameter between 0.1 and 0.65 nm = 100 and 650 pm (1 pm = picometer). An atom is made of electrons surrounding a nucleus whose diameter is even smaller: its size is about 1.8–15 millionths of a nanometer depending upon the element (1.8–18 fm)! Table 1 recalls the different subunits used as we go from the visible macroscopic world to the microscopic world. A nanometer is quite a small length scale. In order to imagine a 1 nm compared to 1 m ( = 109 nanometers) which is a billion larger, let us consider two large distances in our solar system: the distance from the earth to the moon (*360,000 km) and the distance to the sun (*150 millions of km). If we shrink these distances by a factor of 109 we get 36 cm for the ﬁrst distance and 150 m for the second one. The radius of the sun (*696,000 km) becomes 69.6 cm and that of the earth (6,400 km) becomes equal to 6.4 mm. These comparisons show that a

vii viii Presentation of the Book

Table 1 Units and subunits Unit Value in meter Value in meter 1 m (meter) 1 m 100 m 1 centimeter (cm) 0.01 m 10-2 m 1 millimeter (mm) 0.001 m 10-3 m 1 micrometer or micron (lm) 0.000 001 10-6 m 1 nanometer (nm) 0.000 000 001 10-9 m 1 picometer (pm) 0.000 000 000 001 10-12 m 1 femtometer (fm) 0.000 000 000 000 001 10-15 m

Fig. 1 Dividing a cube into nanocubes increases the total surface of the system a lot

nanometer distance is quite a small distance compared to those we are faced at the macroscopic level. Compared with macroscopic systems, surface effects are very important at the nanoscale. The reason for this can be illustrated by considering a cube of side 1 cm, as shown in Fig. 1. The total surface area of this cube is six faces each of dimensions 1 9 1 cm, making a total of 6 cm2. Suppose we divide this cube into small cubes of side 1 nm (Fig. 1). This gives the incredible number of 1021 nanocubes each with a tiny surface area of 6 9 10-14 cm2. However, the total area of these nanocubes amounts to 6,000 meters squared! This corresponds to the surface area of 60 houses of 100 m2. This demonstrates the power of surfaces at the nanoscale. Strictly speaking, nanotechnology should concern building objects from the bottom-up using atoms or molecules. It also makes possible a top-down approach of reducing size and organization from the macroscopic scale. However this vision is extended to a broader domain where it is possible to observe, see, detect, move, and manufacture objects with dimensions in the range of 1–100 nm. This is much less restrictive and opens a wide ﬁeld of applications, some of them being already on the market. Presentation of the Book ix

Fig. 2 Illustration with objects of different length scale and instruments that can be used to observe them

On the other hand, ‘‘nanomaterials’’ is a term used to describe a broad and disparate range of materials containing characteristic features with dimensions below 100 nm. It is the properties of these individual nanoscale features and their organization both at the nanoscale and up to the macroscale that will define the properties of nanomaterial. These features can be organized in random or well- ordered patterns. Confusingly, a ‘‘nanomaterial’’ can be of macroscopic size containing many nano-objects but it can also be an individual object investigated as a material at the nanoscale. A nanomaterial can be a thin film, a thin wire, or a collection of nanoparticles, for example. A nanomaterial is often characterized by a dimension linked either to the dimension of the salient nanofeatures making up the material or to their organization. When some interesting property of a material emerges from this organization or pattern, the combined material may be referred to as a ‘‘nanostructure’’ or a ‘‘nanostructured material’’. The term ‘‘nanomaterials’’ is used to describe objects that have at least one of their dimensions below 100 nm. Nanomaterials encompass a very broad and disparate range of natural and artificial materials. In practice, they can have the form of a thin film, cylinder, or particle. Neither a single human hair, which looks like a cylinder but has a diameter of about 80,000 nm, nor a red cell, can be called nano-objects, even though they look very small. Figure 2 shows different length scales, each separated by a factor of 1,000, with different objects and the instruments that can be used to see details of the object. For example, the size of mountains is of the order of several kilometers and, if we are far away, we use binoculars to observe their details. Most humans have a height below 2 m and we can see them just with our eyes if we are close by. Insects can have a size of a few millimeters or centimeters: they can be observed with a magnifying glass. Red blood cells have a size of a few thousands nanometers and can be observed with a light microscope. Finally, silicon wires of an integrated x Presentation of the Book

Fig. 3 Nanotechnology deals with nanoscale dimensions (1–100 nm). It is a domain at the crossroads between the macroscopic domain governed by classical physics, and the microscopic domain governed by quantum physics circuit (IC) with a transversal size of several nanometers can be seen with a scanning tunneling microscope. Indeed, to emphasize how the instruments for observing nanomaterials get large and complicated but are becoming more available, so it will revolutionize the field. Objects with a size greater than about 100 nm are currently observed and have been studied for decades. Atoms and molecules with dimensions well below a single nanometer are investigated, but indirectly by means of their interactions with other objects. It is only recently that scientists have had the tools to move and manufacture nano-objects in the range of 1–100 nm. The interesting thing is that at this length scale, we are at a crossroads between classical and quantum physics (Fig. 3). Compared with macroscopic objects that have a behavior governed mostly by the classical laws of physics, quantum effects can appear at the nanoscale and are able to completely change some of the properties of objects that we are used to. A direct consequence of such a surface increase is that if we paint an object with a coating containing nanoparticles, the opacity is greatly enhanced; meaning that less paint is needed for a given area. This is also good for the environment because it reduces pollution and the quantity of raw materials needed to manufacture paint. The same is also true when pesticides are applied in agriculture, for example. Another feature occurring as the dimension of a system that reaches the nanoscale domain is the appearance of quantum effects that change some physical effects. The drawback is that it may happen that the function of a device can no longer be performed as the dimensions of the components are now too small. However, the good thing is an opening up of other fields of applications and functionalities such as electron transistors, Coulomb blockade, and quantum cryptography, with new phenomena. Working with nanomaterials and nanocomponents demands for high expertise and complex and expensive equipment. Figure 4 shows the infrastructure of a nanoelectronics laboratory. The twenty-first century will see huge developments in the nanotechnology domain and a large number of applications will be evident in the marketplace. This development is likely to be ongoing, proceeding by steps. Predicted generational steps in the development of nanotechnology are displayed in Fig. 5. Presentation of the Book xi

Fig. 4 This ﬁgure gives an idea of a laboratory working in nanoelectronics, namely a lithography tool from the ASML company. Image courtesy of IMEC (Belgium)

Fig. 5 Different generations of products coming from nanotechnology according to the classi- ﬁcation of M. C. Roco, C. A. Mirkin, and M. C. Hersam, ‘‘Nanotechnology research and directions for societal needs in 2020’’, Springer, 2011 xii Presentation of the Book

The First Generation corresponds to passive nanostructures, such as coatings made of nanomaterials or containing embedded nanoparticles. The Second Generation, which is presently in progress at both research and industrial stages, is about active nanostructures such as those made for drug delivery or nanotransis- tors. Generation Three will deal with more complex structures with several functions, such as nanorobots, for example. Generation Four is devoted to nanosystems built from atoms and molecules. This is a difficult area of research and, in most of the cases, we are far from mass production capability. The final goal is to build systems incorporating nanotechnology in other technologies to produce powerful and cheap devices useful in daily life. This book provides an overview of the many areas where nanotechnology can make a contribution, in sectors as diverse as health care, building construction, security, or energy. Nanotechnology can provide smart coatings for buildings that provide self-cleaning using the same technologies already being applied in sunscreens. Technologies used today for odor prevention in clothing will be further developed using nanotechnology to fabricate bandages that disinfect and protect a wound. Networks of sensors will be available for monitoring the environment and for providing security in public places. It is accepted that there has been adverse publicity about nanotechnology, based on a lack of understanding of what they are, what benefits they provide, and what risks they may pose to our health, and to our environment. Many nanotechnologies will be as safe in application as concrete, steel, and the nanoengineered microprocessors used in our laptop computers. Nevertheless, on the basis of the precautionary principle, technologies using nanomaterials—do need to be carefully assessed for their toxicity, with the same stringent standards of testing and regulation applied to these nanomaterials as to any other new product. In order to ensure the optimum exploitation of nanomaterials, authorities need to work with the industry to develop robust methodologies that secure the confidence of the public. Education about nanomaterials is a prerequisite to a high-value, knowledge-based economy. The book is divided into ten parts; each part is subdivided into chapters (Fig. 6). Nanotechnology consists in exploring and working in the nanoworld. Part I is a basic introduction to this nanoworld. In Chap. 1 we show that it is now possible to see and move atoms and, in Chap. 2, that scientists are able to make nano-objects using different techniques. Since quantum phenomena can emerge at the nanoscale, we introduce, in Chap. 3, a few ideas allowing understanding of this new behavior and the new physics. Nanomaterials have been used for a long time, in coatings, for example, but it is now possible to design them with properties on demand. Part II is devoted to this subject. Chapter 4 describes how using nanomaterials provides better performance and function with less material. This is clearly a priority in a sustainable devel- opmental approach to use materials. Carbon plays a very specific role in the advancement of nanotechnology through fullerenes, carbon nanotubes, and graphene. Chapter 5 is devoted to this subject. Manufacturing nanomaterials on Presentation of the Book xiii

Fig. 6 Plan of the book demand with speciﬁc properties is the role of nanoengineering. Chapter 6 treats this important aspect. Part III covers a broad and important subject: the applications of nanotechnology to information and communication technologies. There is already today an evolution of microelectronics at the nanometer domain. Many of the integrated circuits we are using are now manufactured using technologies where silicon is engraved with features below 100 nm. Chapter 7 addresses this subject. In Chap. 8 we describe the major trends in nanoelectronics while in Chap. 9 we present some emerging quantum devices. Finally, Chap. 10 is devoted to the basic ideas of molecular electronics where nanodevices are built from atoms or molecules in a bottom-up approach. Health is an important subject for all people. We have devoted Part IV to health care and to some of the possibilities of nanotechnology in this domain. The goal in medicine is to ‘‘better see,’’ ‘‘better treat,’’ and ‘‘better repair.’’ Along these lines, Chaps. 11 and 12 treat diagnostics, therapeutics, and regenerative medicine. xiv Presentation of the Book

Connected to health is the question of applications of nanotechnology in the domain of agriculture and food treated in Chap. 13. The environment is today an important item in many societies and this is discussed in Part V. Measuring pollution is an important issue. Chapter 14 introduces sensors for measuring and monitoring chemical or biological products present in the environment. Humans are in constant interaction with air, water, and soil and Chaps. 15 and 16 introduce the contributions which are expected to these sectors by nanotechnology. The question of climate change is also briefly addressed. Part VI addresses the domain of daily life and the impact of nanotechnology in this area. This is relative to the products used at home in daily life (Chap. 17) including cosmetics (Chap. 18) and textiles (Chap. 19). The number of such products exploiting nanomaterials will increase significantly in the near future. Energy is an essential consideration and Part VII is devoted to this subject. It concerns the production of energy, Chap. 20, and also the role of nanotechnology in the use of energy: in housing (Chap. 21) and in road transport (Chap. 22). Industry, defense, and security are also concerned with nanotechnology. Nanomaterials have many industrial applications (Chap. 23) and nanocatalysis allows for more efficient industrial processes (Chap. 24). Issues related to defense and security are important in democratic societies to prevent threats. Chapter 25 deals with these aspects. If nanotechnology provides opportunities for society it has also some risks. This is the subject of Part IX in which we address the problem of risk and toxicity of nanoparticles (Chap. 26), the protection of society and economical aspects enabled by nanotechnology (Chap. 27) and the social impact of nanoscience and nanotechnology (Chap. 28). Finally, Part X draws some conclusions and perspectives on nanotechnology. This book is intended to give a flavor of nanotechnology and its applications. It will swiftly go through different domains where nanotechnology can have present or future applications. Although we did our best to cover the whole subject of nanotechnology, this book is not an encyclopedia. Many things are missing and we merely gave a short introduction of the different subjects without entering into the technical details. There are many books and review articles devoted to specific areas of nanotechnologies where the reader can find more details. We have chosen to address to a wide audience of people interested in science and technology. As far as nanotechnology is concerned, we have focused attention mostly on ‘‘how it can be used’’ rather than ‘‘how it works.’’ The reason is that nanotechnology will be found in a very large number of applications and everybody will be faced with it one day in one form or another. A basic understanding of the domain is therefore helpful. We have enjoyed writing this book and hope that the reader will enjoy reading it. Acknowledgments

The Authors wish to thank all the colleagues, institutes, and companies that have made contributions toward the publication of this book. It would not have been possible without their efforts. The support of the CEA (Commissariat à l’énergie atomique et aux energies energies alternatives) in providing permission to repro- duce many of the diagrams and pictures is greatly acknowledged. We are deeply indebted to Professor Michael Fitzpatrick, the Lloyd’s Register Foundation Chair in Materials Fabrication and Engineering at The Open University, UK, for his work throughout the book in technical and academic editing to ensure a consistent style and accessibility of the book for a non-specialist reader, as well as for numerous technical contributions. One of us (C. N.) is especially grateful to all colleagues from the CEA who helped him to learn the vast domain of nanotechnology. It was a real pleasure to have discussions with them and a privilege to beneﬁt from their experience.

xv Contents

Part I Exploring and Working in the Nanoworld

1 Seeing and Moving Atoms ...... 3 1.1 Atoms Can Be Seen ...... 3 1.2 Atoms Can Be Moved...... 8 1.3 Microscopy ...... 9 1.3.1 Transmission Electron Microscopy ...... 10 1.4 Synchrotron and Neutron Facilities ...... 13 1.4.1 Synchrotron Radiation ...... 15 1.4.2 Neutron Probes ...... 18 1.5 Conclusion...... 22

2 Making Nano-Objects...... 23 2.1 The Top-Down Approach ...... 24 2.1.1 Photoresists ...... 25 2.1.2 e-Beam Lithography ...... 27 2.1.3 Block Copolymer Nanolithography ...... 28 2.1.4 Pen Nanolithography ...... 29 2.2 On-Wire Lithography ...... 30 2.2.1 Nanoimprint Lithography ...... 31 2.3 Nanochemistry ...... 32 2.4 Langmuir–Blodgett Films ...... 33 2.5 Self-assembled Monolayers ...... 34 2.6 Conclusion...... 36

3 Quantum and Mesoscopic Physics ...... 37 3.1 Quantum Mechanics ...... 37 3.1.1 Postulates of Quantum Mechanics...... 38 3.1.2 Measurement ...... 40 3.1.3 Quantization...... 41 3.1.4 Uncertainty Principle...... 42 3.1.5 Spin ...... 43 3.1.6 Quantum Numbers ...... 43 3.1.7 Quantum Tunneling...... 45

xvii xviii Contents

3.1.8 Bosons and Fermions ...... 45 3.2 Mesoscopic Physics ...... 46 3.3 Conclusion...... 48

Part II Nanomaterials

4 Nanomaterials: Doing More with Less...... 55 4.1 Top-Down and Bottom-Up Approaches ...... 56 4.1.1 Top-Down Approaches ...... 56 4.1.2 Bottom-Up Approach ...... 56 4.1.3 Two Approaches with the Same Goal ...... 57 4.1.4 The Nanobulk Stage (10–15 years) ...... 58 4.1.5 The Nanoworld Stage (15–40 years) ...... 59 4.2 Nanostructuration ...... 61 4.3 Classifying Nanostructured Materials ...... 62 4.4 Nanostructured Materials ...... 64 4.4.1 Nanocrystalline Materials...... 66 4.4.2 Dendrimers ...... 67 4.4.3 Metal Organic Frameworks ...... 68 4.4.4 Nanocomposites ...... 69

5 New Forms of Carbon and New Opportunities ...... 71 5.1 New Forms of Carbon...... 71 5.1.1 Buckyballs ...... 71 5.1.2 Nanotubes ...... 73 5.1.3 Graphene ...... 75 5.2 Applications...... 77 5.2.1 Buckyballs ...... 77 5.2.2 Carbon Nanotubes...... 79 5.2.3 Graphene ...... 83

6 Nanoengineering for Material Technology ...... 85 6.1 Structural Nanomaterials ...... 86 6.1.1 Metallic Materials ...... 88 6.1.2 Ceramic Materials...... 88 6.1.3 Polymers ...... 90 6.1.4 Nanostructured Hybrid Organic–Inorganic Materials ...... 91 6.1.5 Engineering with Nanostructural Materials...... 91 6.2 Functional Nanomaterials...... 92 6.2.1 Hybrid Organic–Inorganic Nanomaterials...... 93 6.2.2 Nanostructured Composites ...... 94 Contents xix

6.2.3 Asymmetric Nanoheterostructures ...... 96 6.2.4 From Smart to Intelligent Coatings/Surfaces...... 96 6.2.5 Intelligent Nanomaterials Systems...... 99 6.3 Biomaterials...... 100

Part III Nanotechnology for Information and Communication Technologies

7 From Microelectronics to Nanoelectronics ...... 109 7.1 Shrinking the Components ...... 109 7.2 Moore’s Law ...... 110 7.3 Smart Systems ...... 111 7.4 Transistors ...... 112 7.5 Smaller, Faster, Cheaper ...... 114 7.6 Limiting Issues ...... 117 7.7 Memories...... 117 7.7.1 More and More Storage Capacities ...... 118 7.7.2 New Memory Technologies ...... 120 7.8 Displays...... 124

8 Major Trends in Nanoelectronics ...... 127 8.1 More Moore...... 127 8.2 More than Moore ...... 131 8.3 Heterogeneous Integration ...... 133 8.4 Beyond CMOS ...... 134

9 Emerging Quantum Devices ...... 139 9.1 Beyond the Quantum Wall...... 140 9.2 Coulomb Blockade ...... 140 9.3 The Single Electron Transistor ...... 145 9.4 Applications of Single Electron Transistors ...... 146 9.5 Quantum Dots ...... 147 9.6 Spintronics...... 149 9.7 Quantum Computing ...... 153 9.8 Nanophotonics ...... 154 9.8.1 Controlling Light ...... 155 9.8.2 Photonic Crystals ...... 156 9.8.3 Plasmonics ...... 160 9.8.4 Metamaterials ...... 162

10 Molecular Electronics ...... 165 10.1 Electronic Conduction ...... 167 10.2 The Electrodes ...... 170 10.3 Nanowires ...... 170 xx Contents

10.4 Molecular Diode...... 172 10.5 3-Terminal Device ...... 173 10.6 Conducting Polymers ...... 173 10.7 Oligomers ...... 174 10.8 Polymer Conduction ...... 175 10.9 Self-assembled Monolayers ...... 176 10.10 Conclusion...... 177

Part IV Healthcare

11 Diagnostics...... 189 11.1 Diagnosis and Imaging ...... 191 11.2 From Biochips to Cells-on-Chips ...... 195 11.2.1 A Need for Biosensors...... 195 11.2.2 Biochips ...... 196 11.2.3 Labs-on-Chips ...... 199 11.2.4 Cells-on-Chips ...... 203 11.3 Conclusion...... 206

12 Therapeutics and Regenerative Medicine...... 209 12.1 Therapeutics...... 209 12.1.1 Improved Drug Delivery ...... 209 12.1.2 Delivery Routes ...... 212 12.2 Regenerative Medicine ...... 217 12.2.1 The Quest for Biomaterials ...... 218 12.2.2 Biomimetics ...... 219 12.2.3 Cell Therapy ...... 219 12.2.4 Implants...... 220 12.2.5 Nanotechnology in Surgery ...... 223 12.2.6 Wound Dressing and Smart Textiles ...... 224 12.3 Nanotechnology in Dentistry ...... 224 12.3.1 Nanomaterials for Prevention of Caries ...... 225 12.3.2 Materials for Tooth Repair and Restoration ...... 226 12.3.3 Engineering Dental Implants ...... 226 12.3.4 Reconstruction of Hard and Soft Periodontal Tissues 227 12.3.5 Engineering Tooth Development...... 228 12.3.6 Salivary and Respiratory Diagnostics...... 228 12.3.7 Conclusion ...... 228 12.4 Nanopharmacology ...... 229 12.5 Conclusion...... 231 Contents xxi

13 Nanotechnologies in Agriculture and Food ...... 233 13.1 Agricultural Production ...... 233 13.2 Food Processing ...... 236 13.3 Packaging ...... 239 13.4 Distribution and Transportation ...... 242 13.5 Food Safety ...... 244 13.6 Conclusion...... 245

Part V Nanotechnology for Environmental Engineering

14 Sensors for Measuring and Monitoring ...... 255 14.1 NEMS Technology Development and Applications...... 255 14.2 Nanotechnologies for Detection and Monitoring ...... 257 14.3 Overview of the Possibilities for Nanosensors ...... 259 14.3.1 Health Care ...... 260 14.3.2 Clothing Industry ...... 261 14.3.3 Sensors in the Automotive Industry...... 261 14.3.4 Oil and Gas Exploitation ...... 261 14.3.5 Security ...... 261 14.3.6 Smart Structures ...... 262 14.3.7 Sensors for Environmental Monitoring ...... 263 14.3.8 Food Science ...... 264 14.3.9 Environmental Pollution ...... 264 14.3.10 Farming Industry ...... 265 14.4 Conclusion...... 266

15 Nanotechnology Applications for Air and Soil ...... 267 15.1 Nanotechnology for Air Purification (Artificial Environment Hazards) ...... 267 15.2 Aerosols Nanoparticles ...... 268 15.3 Aerosols Nanoparticles and Climate Change ...... 271 15.4 Soil Remediation ...... 280 15.5 Conclusion...... 281

16 Water Demands for Nanotechnology ...... 283 16.1 Nanotechnology Opportunities ...... 284 16.2 Nanofiltration and Membrane Processes ...... 285 16.3 Nanostructured Ceramic Membranes ...... 285 16.4 Photocatalysis: Organic/Inorganic Hybrid Membranes ...... 287 16.5 Adsorption Mechanism ...... 287 16.6 Nanosensors in Water Analysis ...... 288 xxii Contents

16.7 Removal of Nanoparticles Used in the Purification Process ...... 288 16.8 Conclusion...... 289

Part VI Nanotechnology and Daily Life

17 Products for the Home of the Future ...... 295 17.1 Household Innovation ...... 295 17.1.1 Cleaning and Cleanliness ...... 295 17.1.2 An Energy-Efficient Home...... 297 17.1.3 Sport and Nanotechnology ...... 299 17.2 Personal Hygiene ...... 299 17.2.1 Nanotechnology and Textiles ...... 301 17.3 Healthcare ...... 301 17.3.1 Vaccination and Drug Delivery...... 301 17.3.2 Sunscreens and Skin Protection ...... 302 17.3.3 Nanoatomizer ...... 305 17.4 Nanofoodstuffs ...... 305 17.4.1 Food and Nanotechnology ...... 306 17.4.2 Packaging ...... 308 17.4.3 Drinks ...... 308 17.5 Conclusion...... 309

18 Nanomaterials and Cosmetics ...... 311 18.1 Sunscreens ...... 312 18.2 Cosmetics Delivery ...... 313 18.3 Safety Aspects of Cosmetics ...... 317 18.4 Conclusion...... 319

19 Nanotechnology for the Textile Industry ...... 321 19.1 Toward New Textiles ...... 321 19.1.1 Nanomaterials and Nanocomposites ...... 321 19.1.2 Self-cleaning and Dirt-Free Textiles ...... 322 19.1.3 Medical Textiles ...... 323 19.1.4 Security, Safety, and Military Textiles...... 324 19.1.5 Textiles for Automotive Applications ...... 324 19.1.6 Smart Textiles ...... 325 19.2 Finishing Treatments...... 326 19.3 Conclusion...... 328 Contents xxiii

Part VII Energy and Nanotechnology

20 Nanotechnology and the Energy Challenge ...... 337 20.1 The Energy Challenge ...... 337 20.2 Nanotechnology and Fossil Fuels ...... 339 20.2.1 Petroleum Refining ...... 339 20.2.2 Syngas...... 341 20.3 Nanotechnology and Renewable Energies ...... 342 20.3.1 Solar Energy ...... 343 20.3.2 Nanostructured Photovoltaics ...... 345 20.3.3 Wind Energy ...... 346 20.3.4 Thermoelectricity ...... 346 20.4 Energy Vectors...... 347 20.4.1 Electricity ...... 347 20.4.2 Hydrogen ...... 349 20.5 Energy Storage ...... 351 20.5.1 Electrochemical Storage...... 351 20.5.2 Nanomaterials for Hydrogen Storage ...... 352 20.6 Smart Energy Consumption ...... 352 20.7 Conclusion...... 354

21 Housing ...... 357 21.1 Nanotechnology in Construction Engineering ...... 357 21.1.1 Potential for Nanoconcrete Materials...... 360 21.1.2 Nanocements and Concrete Developments ...... 360 21.1.3 Smart Materials: Building Materials with Multiple Benefits ...... 363 21.1.4 Nanofillers in Construction Engineering...... 365 21.1.5 Textiles in Construction...... 366 21.1.6 Technical Ceramic Materials ...... 366 21.2 Nanotechnology Inside Housing ...... 367 21.2.1 Insulation ...... 368 21.2.2 Nanoporous Materials ...... 368 21.2.3 Radiation Insulation ...... 370 21.2.4 Windows ...... 371 21.3 Nanocoatings ...... 372 21.3.1 Self-cleaning ...... 373 21.3.2 Nanoprotection ...... 374 21.4 Conclusion...... 375

22 Road Transport ...... 377 22.1 Improving Mobility...... 377 22.2 New Functionalities ...... 378 22.3 Outside a Car ...... 380 xxiv Contents

22.3.1 Body Parts ...... 380 22.3.2 Tires ...... 380 22.3.3 Gluing ...... 381 22.3.4 Car Protection ...... 381 22.3.5 Windows and Optics ...... 382 22.4 Inside a Car ...... 383 22.4.1 Nanofilters ...... 383 22.4.2 Nano-Enabled Automotive Textiles ...... 383 22.4.3 Self-cleaning ...... 384 22.5 Power Train ...... 384 22.5.1 Improving Combustion ...... 384 22.5.2 Exhaust Emissions ...... 385 22.5.3 Switchable Materials ...... 385 22.5.4 Supercapacitors...... 385 22.5.5 Batteries ...... 385 22.5.6 Fuel Cells ...... 386 22.6 Conclusion...... 386

Part VIII Nanotechnology in Industry, Defense, and Security

23 Nanomaterials in Industrial Application ...... 393 23.1 Electronics, Information, and Communication ...... 393 23.2 Materials ...... 394 23.3 High-Value Industries ...... 394 23.4 Manufacturing and Processing Industries ...... 396 23.5 Meeting Food and Water Demand ...... 397 23.6 Energy...... 397 23.7 Security ...... 397 23.8 Consumer Products ...... 399 23.9 HealthCare Industries ...... 399 23.10 Magnetic Nanopaper ...... 400 23.11 NanoAdhesives...... 401 23.12 Conclusion...... 402

24 Nanocatalysts: Fascinating Opportunities ...... 403 24.1 What Is a Catalyst?...... 403 24.2 Catalysis and Nanoscience ...... 405 24.3 Catalysis Engineering ...... 407 24.4 What Can Emerge from the Nanoscience of Catalysis? . . . . . 409 24.5 Conclusion...... 410 Contents xxv

25 Nanotechnology for Defense and Security ...... 413 25.1 Detection ...... 413 25.1.1 Chemical Detection ...... 414 25.1.2 Biological Detection ...... 416 25.1.3 Radiological and Nuclear Weapons ...... 416 25.1.4 Explosives ...... 417 25.1.5 Narcotics ...... 418 25.1.6 Counterfeiting...... 419 25.2 Response ...... 419 25.2.1 Prompt Response ...... 419 25.2.2 Decontamination ...... 421 25.2.3 Forensics ...... 421 25.3 Protection ...... 423 25.3.1 Protection of people ...... 423 25.3.2 Protection of Infrastructure and Equipment ...... 424 25.3.3 Anti-counterfeiting ...... 425 25.3.4 Authentication ...... 425 25.3.5 Identification ...... 426 25.4 Nanotechnology and Military Applications ...... 426 25.4.1 Military and Dual Nanotechnology Applications. . . 426 25.4.2 Nanotechnology for Human Beings...... 428 25.4.3 Mobility...... 430 25.4.4 Weapons ...... 431 25.5 Conclusion...... 431

Part IX Nanotechnology: Opportunities and Risks for Society

26 Risks and Toxicity of Nanoparticles ...... 439 26.1 Risks and Hazards ...... 439 26.2 Engineered Nanoparticles and Human Health...... 442 26.3 Toxicity and Risks ...... 444 26.4 Conclusion...... 447

27 Protection of Society and Economical Aspects ...... 449 27.1 Nanomaterials Technology: Safety and Security for the Protection of Society ...... 449 27.1.1 Nanosafety Applications ...... 449 27.1.2 Protection Technologies...... 451 27.1.3 Nanoelectronics: Energy Source ...... 452 27.1.4 Industrial Challenges ...... 452 27.2 Business Aspects and Marketing of Nanotechnologies...... 454 27.3 Conclusion...... 456 xxvi Contents

28 Social Impact of Nanoscience and Nanotechnology: A Perspective ...... 459 28.1 Great Challenges, Promises, and Benefits of Nanomaterials Science and Technology ...... 460 28.2 Positive Effects and Social Benefits of Micro and Nanotechnologies ...... 461 28.3 Societal Acceptance of Micro and Nanotechnology Innovation ...... 462 28.4 Uncertainties, Risks, Incidental Concerns, and Societal Implications of Nanomaterials ...... 464 28.4.1 Uncertainties ...... 464 28.4.2 Relevant Existing Regulatory Standards for Safety...... 464 28.5 Strategies for Improving Governance Practices Associated with Nanotechnologies ...... 465 28.6 Conclusion...... 466

Part X Outlook

29 Outlook ...... 473 29.1 Nano-Objects ...... 474 29.2 Nanomaterials ...... 476 29.3 Nanotechnology in the Home ...... 478 29.4 Nanotechnology in the Industry ...... 479 29.5 Nanoelectronics ...... 480 29.6 Human Health and Aging ...... 482 29.7 Food Security and Sustainable Agriculture...... 484 29.8 Secure, Clean, and Efficient Energy ...... 485 29.9 Smart, Green, and Integrated Transport ...... 486 29.10 Resource Efficiency and Climate Change Action ...... 487 29.11 Inclusive, Innovative, and Secure Societies ...... 488 29.12 Cleaning and Purification...... 488 29.13 Summary ...... 489

Bibliography ...... 491

Index ...... 495 Figures

Fig. 1 Dividing a cube into nanocubes increases the total surface of the system a lot...... viii Fig. 2 Illustration with objects of different length scale and instruments that can be used to observe them ...... ix Fig. 3 Nanotechnology deals with nanoscale dimensions (1–100 nm) ...... x Fig. 4 This figure gives an idea of a laboratory working in nanoelectronics, namely a lithography tool from the ASML company ...... xi Fig. 5 Different generations of products coming from nanotechnology according to the classification of M. C. Roco, C. A. Mirkin, and M. C. Hersam, ‘‘Nanotechnology research and directions for societal needs in 2020’’, Springer, 2011 ...... xi Fig. 6 Plan of the book...... xiii Fig. I.1 Artist’s impression of the principle of a scanning tunnel microscope...... 1 Fig. 1.1 Principle of a scanning tunneling microscope (STM) . . . . . 4 Fig. 1.2 Schematic illustration of the two operating modes of the STM: the constant height mode and the constant-current mode ...... 4 Fig. 1.3 STM image of a silicon surface when the crystal is oriented along the (111) plane, bright dots correspond to surface Si-atoms ...... 5 Fig. 1.4 Artist’s impression view of the principle of an atomic force microscope (AFM)...... 6 Fig. 1.5 Compilation from http://en.wikipedia.org/wiki/ Scanning_probe_microscopy of scanning probe microscopy techniques ...... 7 Fig. 1.6 Atoms of xenon moved on the surface of a nickel crystal and arranged in order that IBM, the name of the Company, appears to be written ...... 8 Fig. 1.7 Quantum coral ...... 8

xxvii xxviii Figures

Fig. 1.8 Principle (simplified) of transmission and scanning electron microscopes...... 10 Fig. 1.9 Schematic representation of a most modern microscope, Image courtesy of G. Van Tendeloo, UIA Antwerpen, (Belgium) ...... 12 Fig. 1.10 Applications of transmission electron microscopy (TEM) ...... 13 Fig. 1.11 High-resolution image of a palladium catalyst deposited onto a membrane of amorphous carbon membrane ...... 14 Fig. 1.12 Multiwall carbon nanotube grown on an iron oxide catalyst...... 14 Fig. 1.13 Chemical image of interconnections in an integrated circuit made at CEA/LETI...... 15 Fig. 1.14 Chemical mapping of small magnetic particles of FeNi constructed from three chemical images ...... 16 Fig. 1.15 Individual atoms in a gold nanoparticle with fivefold symmetry ...... 16 Fig. 1.16 Individual atoms in a gold nanobar...... 17 Fig. 1.17 Nanobar where the nucleus and the exterior (coating) consist of different materials ...... 17 Fig. 1.18 Collection of semiconductor nanoparticles forming chains ...... 18 Fig. 1.19 Main advantages of synchrotron radiation sources ...... 19 Fig. 1.20 Main techniques using synchrotron radiation and the type of information that can be obtained ...... 19 Fig. 1.21 Some applications of neutrons to nanoscale analysis. . . . . 20 Fig. 1.22 Main questions that should be asked in studying nano-objects...... 21 Fig. 2.1 Difference between a top-down and a bottom-up approach ...... 24 Fig. 2.2 Different stages in a lithography process during one masking level...... 25 Fig. 2.3 Principle of lithography using a positive and a negative photoresist ...... 26 Fig. 2.4 Principle of immersion lithography...... 28 Fig. 2.5 Schematic illustration of a diblock polymer ...... 29 Fig. 2.6 Different pen nanolithography techniques ...... 29 Fig. 2.7 Principle of on-wire lithography...... 31 Fig. 2.8 Principle of thermal nanoimprint lithography ...... 32 Fig. 2.9 Principle of the preparation of Langmuir- Blodgett films ...... 34 Fig. 2.10 Schematic drawing of multilayers obtained with the Langmuir-Blodgett technique on a specific substrate. . . . . 34 Figures xxix

Fig. 2.11 Schematic drawing of a tail-to-head structure of three monolayers made by the Langmuir–Blodgett method on a hydrophilic surface...... 35 Fig. 2.12 Representation of a self-assembled monolayer ...... 35 Fig. 3.1 Comparison between classical and quantum mechanics . . . 38 Fig. 3.2 Wave-particle duality ...... 39 Fig. 3.3 Harmonic oscillator potential ...... 41 Fig. 3.4 Spatial boundary conditions lead to energy quantization (discrete energy levels) ...... 42 Fig. 3.5 Schematic illustration of quantum tunneling ...... 45 Fig. 3.6 Fermions cannot be in the same quantum state ...... 46 Fig. 3.7 At the nanoscale, fluids behave more like honey than water ...... 47 Fig. I.1 Nano-objects can be made by top-down or bottom-up manufacturing ...... 50 Fig. I.2 Interplay between theory and experiment of nano-objects in nanotechnology progress ...... 50 Fig. II.1 Particles (in red) are coated onto the surface of a material (blue)...... 52 Fig. II.2 Characterization is the backbone of material studies . . . . . 52 Fig. 4.1 Top-down nanosynthesis methods...... 57 Fig. 4.2 Bottom-up methods for nanosynthesis ...... 57 Fig. 4.3 Bottom-up fabrication of nanocomposite magnets...... 58 Fig. 4.4 Schematic position of top-down and bottom-up fabrication mechanisms for nanoelectronics. Image courtesy of IMEC (Belgium) ...... 58 Fig. 4.5 Roadmap for improvements in nanotechnology ...... 60 Fig. 4.6 Convergence from Top-down and Bottom-up approaches in the case of nanoelectronics ...... 60 Fig. 4.7 Properties of nanoscale building blocks which will have tremendous consequences for nanostructured materials . . . 61 Fig. 4.8 Nanostructuration of platinum in the form of nanoparticles ...... 62 Fig. 4.9 Nanostructuration of platinum in the form of porous nanotubes ...... 62 Fig. 4.10 Classification where 1D, 2D, and 3D objects have one, two, or three dimensions in the nanometer range ...... 63 Fig. 4.11 Classification of materials according to the dimensionality of the nanostructures ...... 64 Fig. 4.12 Different types of nanomaterials according to their composition ...... 64 Fig. 4.13 Transverse view of a thin film of FeHf(N,O) nanostructured material ...... 66 Fig. 4.14 Families of nanostructured materials ...... 66 xxx Figures

Fig. 4.15 Schematic synthesis of a dendrimer by the divergent method ...... 68 Fig. 4.16 There can be sophisticated architectures of dendrimers . . . 68 Fig. 5.1 Schematic representation of a C60 molecule...... 72 Fig. 5.2 Schematic picture of a closed single-walled carbon nanotube ...... 73 Fig. 5.3 Schematic drawing of a carbon nanotube obtained by rolling up a graphene sheet, closed at the two ends by half of a fullerenes ...... 74 Fig. 5.4 Scanning electron microscope images of carbon nanotubes on a silicon substrate grown in a reactor attheCEA...... 74 Fig. 5.5 Graphene plane from which a single-walled nanotube is formed by rolling up the sheet ...... 76 Fig. 5.6 Difference between zigzag and armchair forms of carbon nanotubes as seen by looking along the symmetry axis of the nanotube ...... 77 Fig. 5.7 Different types of engineering of fullerene molecules . . . . 78 Fig. 5.8 Some actual and potential applications of carbon nanotubes ...... 79 Fig. 5.9 Aligned carbon nanotubes after growth on a silicon wafer of 300 mm ...... 80 Fig. 5.10 Self-supporting carbon nanotube membrane obtained after removing the silicon wafer...... 81 Fig. 5.11 Carbon nanotube forests ...... 81 Fig. 5.12 Experiment to tune the electronic properties of graphene ...... 83 Fig. 5.13 Some domain of application of graphene, among others, as shown ...... 84 Fig. 6.1 Applications of nanotechnology in the aircraft sector . . . . 86 Fig. 6.2 Dissolved nanoparticles from noble metals show different colors depending on the size...... 86 Fig. 6.3 Overview of nanomaterials ...... 87 Fig. 6.4 Overview of structural nanomaterials ...... 87 Fig. 6.5 Nanoceramics in diesel filters for exhaust gases ...... 89 Fig. 6.6 Multilayered Ti-rich/Sn-rich oxides with coherent interfaces parallel rutile (001) planes ...... 89 Fig. 6.7 Use of polymers in the design of nanomaterials ...... 90 Fig. 6.8 L. Giannini–Pirelli Tyre S.p.A.—Nanorubber-tyres for automobile application—Pirelli experience— ANFIA Torino April 2010...... 90 Fig. 6.9 How nanostructures change the flow properties ...... 91 Fig. 6.10 Principles in designs with structural nanomaterials ...... 92 Figures xxxi

Fig. 6.11 Overview of functional nanomaterials ...... 93 Fig. 6.12 Rubber clay nanocomposite reinforced rubber compounds for tire applications...... 94 Fig. 6.13 Nanocomposites for improved barrier properties...... 95 Fig. 6.14 Asymmetric nanoheterostructure model...... 96 Fig. 6.15 Three types of coating used in the aerospace industry. . . . 97 Fig. 6.16 From smart to intelligent materials coatings...... 98 Fig. 6.17 Nanostructured turbine blade coatings that contain healing agents ...... 99 Fig. 6.18 From nanomaterials properties to innovative products. . . . 100 Fig. 6.19 Bio-nanomaterials spectrum ...... 101 Fig. III.1 300 mm silicon wafer with integrated circuits manufactured on it ...... 107 Fig. 7.1 Number of transistors contained in different Intel processors as a function of their year of introduction on the market...... 110 Fig. 7.2 Propagation, for a 1-dimensional lattice of electrons, of a hole (site where an electron is missing) ...... 112 Fig. 7.3 Diagram of an n-channel junction field-effect transistor (FET or JFET) ...... 113 Fig. 7.4 Hydraulic analogy illustrating the operating conditions of a field-effect transistor ...... 114 Fig. 7.5 This figure shows a 22, 300, and 450 mm silicon wafer ...... 116 Fig. 7.6 Printing analogy to illustrate the evolution of the size of wafers and progresses of lithography used in microelectronics ...... 116 Fig. 7.7 Evolution of the semiconductor manufacturing processes in log scale ...... 117 Fig. 7.8 Main types of memories extensively used in computers ...... 119 Fig. 7.9 Mean evolution of the hard drive cost per gigabyte over three decades ...... 120 Fig. 7.10 Schematic difference between transverse magnetization (top) and perpendicular magnetization (bottom)...... 120 Fig. 7.11 Magnetic force microscopy image of 100–200 nm magnetic domain structures made up of a multilayer of Pt and Co deposited on a pre-etched silicon substrate ...... 121 Fig. 7.12 Some new memory developments where nanotechnology plays a significant role ...... 121 Fig. 7.13 SRAM produced by the Crolles 2 Alliance using the 65 nm technology node on a 0.5 lm2 surface area . . . 122 xxxii Figures

Fig. 7.14 Basic principle of a racetrack memory developed by IBM ...... 123 Fig. 7.15 Main display technologies used today ...... 123 Fig. 7.16 Main technologies for video display ...... 124 Fig. 8.1 The four main domains of R&D according to the ObservatoryNano project ...... 128 Fig. 8.2 Different point of improvement in the ‘‘More Moore’’ . . . 128 Fig. 8.3 Some innovation challenges that should be investigated for the More Moore domain...... 129 Fig. 8.4 FinFET SEM/TEM pictures ...... 130 Fig. 8.5 High mobility FinFETs for the 10 and 7 nm generations. . 130 Fig. 8.6 Nondigital functions that should be useful for device integration ...... 132 Fig. 8.7 Several analog information is useful to measure using micro and nanotechnologies...... 132 Fig. 8.8 Subjects in the ‘‘More than Moore’’ domain, where nanotechnology can be involved...... 133 Fig. 8.9 Electromechanical component formed by a nanotube suspended between two gold electrodes...... 134 Fig. 8.10 Schematic illustration of the evolution of the mean free path as the dimension of the container decreases ...... 135 Fig. 8.11 Multigate MOS architecture with metal source/drain carrying extensions increasing the charge carrier injection speed into the channel (CEA-Leti patents) . . . . . 136 Fig. 8.12 Transmission electron microscope views of a 20 nm (left part of the figure) and 10 nm (right part of the figure) double-gate transistors fabricated at the Leti to better control leakage current between source and drain...... 136 Fig. 8.13 Diagram of a metal/semiconductor/metal intramolecular junction with predicted stability ...... 137 Fig. 9.1 If the two electrodes (in blue) are not charged electrically, an electron cannot spontaneously go across the insulator junction (in red) because it costs a lot of energy ...... 141 Fig. 9.2 If the two electrodes (in blue) are charged electrically with e/2...... 142 Fig. 9.3 About the 3 parts (1), (2) and (3) of the figure ...... 143 Fig. 9.4 The field effect of two grids, manufactured by nanolithography and evaporated above the surface of a conductor containing an electron layer, can be used to define a constriction of adjustable width ...... 144 Fig. 9.5 Principle of a single electron transistor ...... 145 Fig. 9.6 Picture of a single electron field-effect transistor ...... 146 Fig. 9.7 Possible applications of single electron transistors ...... 147 Figures xxxiii

Fig. 9.8 Schematic illustration of the size influence on quantum dot emission ...... 148 Fig. 9.9 Semiconductor nanocrystals of different sizes illuminated with ultraviolet light ...... 148 Fig. 9.10 Quantum dot separated from the contacts by a tunnel barrier ...... 149 Fig. 9.11 An electron e- in a magnetic field has two possible orientations associated with different energies, one called spin-up, aligned with the magnetic field, and one with spin-down (anti-parallel to the magnetic field) . . 150 Fig. 9.12 In the left-hand part, spins are oriented at random while, in the right-hand part, they are aligned along a strong applied external field ...... 150 Fig. 9.13 In the case of a crystal where the spins are located at the sites, the spins can be oriented at random in the case of an unmagnetized material or aligned if the material is magnetized...... 151 Fig. 9.14 Schematic illustration of magnetic tunnel junction of two ferromagnetic layers separated by a thin barrier layer ...... 151 Fig. 9.15 Illustration of magnetic tunnel junction composed of two ferromagnetic layers separated by a thin barrier layer ...... 152 Fig. 9.16 Sectors where spintronics can play a role ...... 152 Fig. 9.17 Nanophotonics encompasses several nanoscale confinements indicated in the figure ...... 155 Fig. 9.18 Block diagram representing the main fields and applications in nanophotonics...... 156 Fig. 9.19 Drawing of different light confinement which can be performed in nanophotonics...... 157 Fig. 9.20 Formation of semiconductor nanowires via vapor– liquid–solid growth mechanism, first introduced by Wagner and Ellis at Bell Labs in 1964 ...... 157 Fig. 9.21 It is possible to play on several parameters to make photonic crystals with required properties ...... 159 Fig. 9.22 Two schematic examples of waveguides using photonic crystals...... 161 Fig. 9.23 Local probe view (known also as a near-field image) of the optical wave propagating in a photonic crystal waveguide ...... 162 Fig. 9.24 Possible applications of metamaterials ...... 162 Fig. 10.1 Some advantages of molecular electronics...... 167 Fig. 10.2 Ethane, ethene, and ethyne molécules ...... 167 Fig. 10.3 Stick-and-ball models of H2O and CO2 molecules ...... 168 xxxiv Figures

Fig. 10.4 Schematic representation of the band structure of metals, insulators, and semiconductors ...... 169 Fig. 10.5 Crossover of two carbon nanotubes deposited on silica, illustrating the productionof nanotube circuits by self-assembly...... 170 Fig. 10.6 Principle of a molecular wire...... 170 Fig. 10.7 Scanning electron microscope image showing silicon nanowires with a diameter in the range of 30–100 nm synthesized by the vapor–liquid–solid technique...... 171 Fig. 10.8 Basic principle of a molecular diode...... 172 Fig. 10.9 Different charge transport mechanisms in molecular wires made of organic materials...... 175 Fig. 10.10 Self-assembled monomolecular layer of dodecanethiol on a single gold crystal viewed by tunneling microscopy ...... 176 Fig. 10.11 Illustration of self-assembled monolayer deposition via surface active molecules ...... 177 Fig. 10.12 Carbon nanotubes (pink) linked to DNA strands (black)...... 177 Fig. III.1 Evolution of the physics as we go from macroscopic systems to microscopic systems ...... 180 Fig. III.2 Highlights of the potentials and weaknesses in nanoelectronics...... 181 Fig. IV.1 Overview of nanotechnology in life sciences ...... 184 Fig. IV.2 Packaged NEMs (nano-electro-mechanical) sensors . . . . . 185 Fig. IV.3 Wireless transmission of an ECG signal ...... 186 Fig. 11.1 Major diseases touching a large proportion of the population ...... 190 Fig. 11.2 Solutions for human attacks: heart and brain scanning . . . 191 Fig. 11.3 Magnetic nanoparticles: Design and characterization, toxicity and biocompatibility, pharmaceutical and biomedical applications ...... 191 Fig. 11.4 Schematic example of using a wireless capsule to perform endoscopy ...... 193 Fig. 11.5 Different steps that can be used to cure cancer ...... 194 Fig. 11.6 Self-Assembled Squalenoylated Penicillin Bioconjugates: An Original Approachor the Treatment of Intracellular Infections ...... 195 Fig. 11.7 Schematic illustration of a DNA chip array ...... 198 Fig. 11.8 Example from fluorescence scanning of a DNA chip . . . . 199 Fig. 11.9 Several cells where many cellular phenotypes can be recorded in biological reactions made in parallel on the biochip...... 200 Figures xxxv

Fig. 11.10 In this biochip, there are hundreds of biological molecules fixed on the internal wall of a capillary ...... 200 Fig. 11.11 Silicon microcomponent for liquid chromatography . . . . . 202 Fig. 11.12 Device developed by CEA and ST-Microelectronics dedicated to genetic diagnosis ...... 203 Fig. 11.13 Microsystem allowing manipulation of 100-nanoliter droplets by electrowetting ...... 203 Fig. 11.14 Lab-on-chip device that acts as a cell sorter ...... 204 Fig. 11.15 Section of an electrode network in which electric potential traps have been designed to trap particles . . . . . 205 Fig. 11.16 Chip with cells organized in the trap (insert) ...... 205 Fig. 11.17 Main benefits that nanotechnology can bring to diagnosis ...... 206 Fig. 11.18 Categories of biosensors relying on micro and nanoelectronics and micro and nanotechnology ...... 206 Fig. 12.1 The main expected advantages of nanotechnology delivery of drugs ...... 210 Fig. 12.2 Methods of drug delivery ...... 211 Fig. 12.3 Schematic representation of a micelle and a vesicle . . . . . 211 Fig. 12.4 Principle of imprinted polymers ...... 212 Fig. 12.5 Some therapeutics based on nanotechnology ...... 213 Fig. 12.6 Different fields of polymer therapeutics ...... 214 Fig. 12.7 Nanoparticles with in vivo anticancer activity from polymer prodrug amphiphiles prepared by living radical polymerization ...... 215 Fig. 12.8 Basic steps toward regenerative tissue engineering ...... 218 Fig. 12.9 Basic ingredients in regenerative medicine ...... 220 Fig. 12.10 Schematic principle of an artificial retina ...... 223 Fig. 12.11 Various elements of the tooth structure, Image courtesy of GSK, Dusseldorf ...... 225 Fig. 12.12 Present applications of nanotechnology in dentistry with growing turnover...... 225 Fig. 12.13 Cavity repair: nanocomposites for aesthetics, strength and longevity ...... 226 Fig. 12.14 Dental root implants: nanotextured surfaces and coatings for more rapid boneand soft tissue bonding ...... 227 Fig. 12.15 Enhanced photodisinfection of periodontal pathogens . . . . 227 Fig. 12.16 Highlight the needs for further developments in this important field ...... 229 Fig. 12.17 Principle of nanoparticles for therapy ...... 230 Fig. 12.18 Main benefits expected from nanotechnology...... 231 Fig. 12.19 Discovery of new hexagonal supramolecular nanostructures formed by squalenoylation of an anticancer nucleoside analog ...... 232 xxxvi Figures

Fig. 12.20 Summary of challenges in nanomedicine...... 232 Fig. 13.1 Scaling of biomaterials ...... 234 Fig. 13.2 Different topics relevant to agriculture and food...... 234 Fig. 13.3 Main challenges for nanoagriculture ...... 235 Fig. 13.4 Risks issues in agriculture nanotechnology ...... 236 Fig. 13.5 Agriculture as a source of food and industrial products. . . 236 Fig. 13.6 Challenges for nanoagrifoods ...... 237 Fig. 13.7 Beneficials and risks issues in food processing and production nanotechnology ...... 238 Fig. 13.8 Nanomaterials for nutrients delivery ...... 239 Fig. 13.9 Challenges for nanotechnology in food packaging nanotechnology ...... 240 Fig. 13.10 Risk issues in food packaging nanotechnology...... 241 Fig. 13.11 Future vision of smart food freshness labels ...... 242 Fig. 13.12 Active antimicrobial packaging ...... 243 Fig. 13.13 What is the holy grail in green packaging ...... 243 Fig. 13.14 Challenges for nanoagrifoods in food distribution and transport nanotechnology...... 244 Fig. 13.15 Summary of benefits for nanotechnologies in agriculture and food ...... 247 Fig. IV.1 Some domains of medicine where nanotechnology can be useful ...... 250 Fig. IV.2 Sectors where clinicians wait for progress using nanotechnology ...... 250 Fig. IV.3 Environmental protection address three main a role . . . . . 251 Fig. V.1 Environmental protection address three main areas: air, water and soil...... 254 Fig. V.2 Schematic representation of the benefits of nanotechnology for the environment ...... 254 Fig. 14.1 Example of domains where nanosensors can play a role ...... 256 Fig. 14.2 Shows the interplay between the difference technologies: nano-, bio-, infotechnologies and cognition ...... 256 Fig. 14.3 Nanoelectronic nose where nanoelectronics is used to mimic the sniffer dog ...... 258 Fig. 14.4 Research topics that are associated to the artificial nose concept ...... 259 Fig. 14.5 Example of the integration of massive parallelized nanosensors (left hand side), here probe-microscopy tips, into a silicon based prototype microdevice for storagepurposes (right hand side) ...... 260 Fig. 14.6 Scheme of a nanobiodetector ...... 260 Fig. 14.7 Application of sensors in cars ...... 262 Fig. 14.8 Strength monitoring of a bridge with nanosensors ...... 263 Figures xxxvii

Fig. 14.9 Sensors and diagnostics in precise agriculture ...... 265 Fig. 14.10 Sensors can be used in many fields ...... 266 Fig. 15.1 Air particulate distribution...... 268 Fig. 15.2 Particle loading in pollution related to mortally ...... 269 Fig. 15.3 Nanoparticles are generated by human activities ...... 269 Fig. 15.4 Overview of the end-of-life cycle approach ...... 271 Fig. 15.5 Synergy in an industrial pilot plant in operation Industrial Ecosystem at Kalundborg Denmark, from http://newcity.ca/Pages/industrialecology.html ..... 272 Fig. 15.6 Human activities have changed the composition of the atmosphere since the pre-industrial era ...... 273 Fig. 15.7 Global-average radiative forcing estimated changes and ranges between 1,750 and 2,005...... 275 Fig. 15.8 Long-range transport of aerosols and gases ...... 276 Fig. 15.9 Overview of the aerosols cycle and key-related processes includes emission of primary particles and gas-phase precursors, nucleation, coagulation, condensation, evaporation, cloud processing, sedimentation dry deposition and wet scavenging ...... 276 Fig. 15.10 Different types of aerosol particles in the air and their size distribution with different modes ...... 277 Fig. 15.11 Natural and industrial sources of aerosols ...... 277 Fig. 15.12 Satellite view of North China on a clear day ...... 278 Fig. 15.13 Satellite view of North China on a polluted day, grey colors are due to aerosols formed by atmospheric chemical processes from anthropogenic emissions ...... 279 Fig. 15.14 Nanoparticles emitted from ship emissions produce more droplets in marine clouds ...... 279 Fig. 15.15 Nanotechnology for soil remediation...... 281 Fig. 15.16 Potential air freshener sensor ...... 282 Fig. 16.1 There are two categories of nanomembranes ...... 285 Fig. 16.2 Plastic membrane with nanoscale pores for water purification ...... 286 Fig. 16.3 Nanopores within the membrane are able to successfully trap bacteria, viruses, and germs successfully out ...... 286 Fig. 16.4 Ceramic membrane modules ...... 287 Fig. V.1 Overview of environmental treatments using nanoparticles ...... 292 Fig. 17.1 Nanotechnology in the house of the future ...... 296 Fig. 17.2 Application of nanotechnology-based paints ...... 296 Fig. 17.3 Importance of antimicrobial coatings ...... 297 Fig. 17.4 Self-healing application of nanocoating for automotive parts...... 298 Fig. 17.5 Some layouts of light-emitting diodes ...... 298 xxxviii Figures

Fig. 17.6 Necklace for long-term and robust cardiac monitoring in sports life ...... 300 Fig. 17.7 Mechanism in healing tooth problems...... 300 Fig. 17.8 Necklace for long-term and robust cardiac monitoring in daily life ...... 302 Fig. 17.9 Three main families of skin cancer...... 303 Fig. 17.10 New generation of UV filters provide reliable all-round protection for the whole day-protecting and caring for the skin ...... 304 Fig. 17.11 Even in the half-shade, we are exposed to UV rays . . . . . 305 Fig. 17.12 Different families of nutrient which can be found in food and some examples of food containing them ...... 307 Fig. 17.13 Base elements for food constructions ...... 307 Fig. 17.14 Nanovisions for bottled products ...... 309 Fig. 18.1 Applications of nanotechnology in cosmetics and a picture of zinc oxide nanoparticles picture in cosmetics...... 312 Fig. 18.2 Two main fields in cosmetics where nanotechnology applies ...... 312 Fig. 18.3 Different delivery systems that can be used in cosmetics...... 314 Fig. 18.4 Schematic illustration of an emulsion of two immiscible liquids ...... 315 Fig. 18.5 On left-hand part of the figure a lipid monolayer is enclosing a liquid lipid core ...... 316 Fig. 18.6 Some causes of nanotoxicity and some of the consequences ...... 318 Fig. 18.7 Different types of nanostructures used in cosmetics . . . . . 319 Fig. 19.1 Mimicking the effect of the lotus leaf in cleaning natural surfaces ...... 323 Fig. 19.2 Multipurpose applications for smart textiles...... 326 Fig. 19.3 Surface properties of textiles or fibers which are interesting for applications...... 327 Fig. 19.4 Main processes used in finishing of textiles...... 328 Fig. 19.5 Some properties of nanocomposite fibers which currently exist or are under development ...... 329 Fig. 19.6 Nanomaterials and nanocomposites used as fillers in textiles ...... 329 Fig. VI.1 The aspects of our daily life ...... 332 Fig. VII.2 Share of final energy consumption in the transport sector for the year 2010 ...... 334 Fig. VII.2 Share of the different energy sources used in the industry sector for the year 2010 ...... 334 Figures xxxix

Fig. 20.1 Total primary energy supply in the world for year 2009 ...... 338 Fig. 20.2 Energy challenge: constraints and solutions ...... 339 Fig. 20.3 In petroleum refining, nanocatalysts are used in four major processes ...... 340 Fig. 20.4 Four major reactions where syngas is involved ...... 341 Fig. 20.5 Four domains where nanotechnologies are involved . . . . . 343 Fig. 20.6 Thin film silicon solar cell...... 344 Fig. 20.7 Organic solar cell on glass substrate ...... 345 Fig. 20.8 Future vision of fordable lights based on OLEDs ...... 349 Fig. 20.9 Two domains of electricity storage where nanotechnologies have a key role ...... 352 Fig. 20.10 Perspectives of nanomaterials in the energy domain . . . . . 354 Fig. 20.11 Primary energy sources. The total primary energy supply in 2010 was 12,717 Mtoe ...... 354 Fig. 21.1 Concrete prefabrication: set-up of the Rosenthal bridge at Olpe in Germany on11/14/2012 ...... 359 Fig. 21.2 Mercury intrusion porosimetry (MIP): GGBS untreated (black) and HKP-GGBS formulas (red and blue)...... 359 Fig. 21.3 a strength profile of Future Concrete ‘‘Futur Beton’’. b CO2-emission caused by the manufacturing of HKP-GGBS, future cement ‘‘Futurzement’’ C.1 and ordinary portland cement (OPC). c smaller demonstrator of about 10 tons setup at Siegen in Germany on 6/21/2013 ...... 359 Fig. 21.4 Scale effect in building materials and structural design . . . 361 Fig. 21.5 Nanoparticle distribution in the nanoconcrete...... 361 Fig. 21.6 Possibilities of using nanomaterials in cement and concrete ...... 362 Fig. 21.7 Effect of nanosized particles (‘‘hybrid vesicles’’) on the permeability of cement paste (after Koleva et al.) ...... 363 Fig. 21.8 Photocatalysis for cleaning air and walls: silica nanoscale particles embedded in an organic polymer matrix...... 364 Fig. 21.9 Inorganic nanoparticles homogeneously incorporated in polymers provide ideal features for facade coatings . . . 364 Fig. 21.10 Scanning electron micrograph of the cured isolation mortar: the black rubbergranules with different particle sizes are embedded in a cement matrix ...... 365 Fig. 21.11 Applying a nanocoating is straightforward: just spread and de-aerate ...... 367 Fig. 21.12 a Al2O3-SiC nanocomposite powder, TEM Image Courtesy Zoz group, Germany. b Al2O3 nanostructured plasma spray coating, TEM...... 367 xl Figures

Fig. 21.13 Heat transfer can occur by conduction, convection, or radiation ...... 368 Fig. 21.14 Insulating foams with nanoscale pores ...... 369 Fig. 21.15 TiO2 self-cleaning surface and the mechanism of operation ...... 372 Fig. 21.16 Nanocoatings have applications in several areas...... 372 Fig. 21.17 Nanotechnology improves characteristics of fabrics . . . . . 374 Fig. 21.18 Different stages in the life cycle of a house...... 376 Fig. 22.1 Nanotechnology can be involved in four main areas of the automobile sector: safety, comfort, environment and performance ...... 378 Fig. 22.2 Different functionalities offered by nanotechnology which can be applied to the automobile sector ...... 379 Fig. 22.3 Overview of possible application fields of nanotechnology in the automobile sector ...... 379 Fig. 22.4 Nanotechnology is expected to bring improvements and breakthroughs in the areas indicated in the figure. . . . 387 Fig. VII.1 Different sectors of the energy domain where nanotechnology can be useful ...... 390 Fig. 23.1 Developments in semiconductor technology...... 394 Fig. 23.2 Overview of spin-off applications of silicon-based nanoelectronics...... 395 Fig. 23.3 Overview of nanomaterials and components in aircraft . . . 395 Fig. 23.4 ‘‘A journey into the future’’: Prospects of nanotechnology in aircraft engineering ...... 396 Fig. 23.5 Effect of nanocarbon particles in automotive tires ...... 398 Fig. 23.6 Nanomaterials in diesel exhaust applications ...... 398 Fig. 23.7 Application of nanotechnology in health care...... 399 Fig. 23.8 Industries researching and using nanotechnology ...... 401 Fig. 24.1 Principle of catalysis...... 404 Fig. 24.2 Difference between homogeneous and heterogeneous catalysis ...... 404 Fig. 24.3 Main functions of a good catalyst...... 405 Fig. 24.4 Properties that a catalyst should have ...... 405 Fig. 24.5 The efficiency of a catalyst depends on several parameters ...... 405 Fig. 24.6 Nanocatalysts for exhaust reduction in cities ...... 406 Fig. 24.7 Main fields of catalysis ...... 407 Fig. 24.8 Summary of the role of catalysts in multiple technologies...... 408 Fig. 24.9 Challenges for heterogeneous catalysis using nanoparticles ...... 409 Fig. 24.10 Applications of nanocatalysts ...... 410 Figures xli

Fig. 25.1 Main sectors in the defense and security domain where nanotechnology can play a role ...... 414 Fig. 25.2 Main sectors where detection is needed...... 414 Fig. 25.3 Different families of toxins ...... 415 Fig. 25.4 Different methods to detect chemicals where nanotechnology can contribute ...... 415 Fig. 25.5 Examples of biological agents that could be used in biological weapons ...... 417 Fig. 25.6 Some families of detection methods available to detect explosives ...... 418 Fig. 25.7 Some responses to various attacks as compiled from the ObservatoryNano project ...... 420 Fig. 25.8 Some applications of scanning electron microscopy in forensics ...... 422 Fig. 25.9 Protection of infrastructures against the three main threats where nanotechnology can play a role: mechanical destruction of structures, fire and electromagnetic interference...... 424 Fig. 25.10 Main anti-counterfeiting techniques based on nanotechnology (list from the ObservatoryNano project) ...... 425 Fig. 25.11 Civilian applications and military applications have a common domain corresponding to so-called dual applications ...... 427 Fig. 25.12 Different applications of nanotechnology in the military domain are shown ...... 427 Fig. 25.13 Dual use of nanotechnology...... 428 Fig. 25.14 Areas where nanotechnology can play a significant role in the equipment of future warriors ...... 429 Fig. 25.15 Nanotechnology is involved in many of the components of the equipment of the warrior of the future ...... 429 Fig. 25.16 Different aspects of mobility for the military ...... 430 Fig. 25.17 Classification of satellites ...... 431 Fig. 25.18 Some areas where nanotechnology can improve weapons ...... 431 Fig. 25.19 Benefits enabled by nanotechnology in the military domain ...... 432 Fig. VIII.1 Some sectors where there are industrial application of nanotechnology ...... 433 Fig. VIII.2 Some intrinsic properties of catalysts and the effect of interface properties on their efficiency ...... 434 Fig. VIII.3 Management of different threats...... 434 Fig. IX.1 Scale effect of components from meter to nanometer . . . . 438 xlii Figures

Fig. 26.1 Loosely speaking the risk is the product of the danger and the hazard ...... 440 Fig. 26.2 Different interactions of workers and users with pollution due to nanoparticles ...... 441 Fig. 26.3 Risks roadmap of nanoparticles ...... 442 Fig. 26.4 Inhalation exposure of nanoparticles: risk assessment . . . . 443 Fig. 26.5 Nanotoxicology ...... 446 Fig. 26.6 NanoToxicology: industry–government standardisation procedure ...... 447 Fig. 26.7 Classification of nanomaterial according to their location in the object ...... 448 Fig. 27.1 Nanosystems for the safety, security, and environmental protection of the human being ...... 451 Fig. 27.2 Continuous decrease of power needs per circuit and the increase of scavenging allow micro- and nanodevice operation without batteries...... 452 Fig. 27.3 Source: MEDEA?report on Energy Autonomous Systems: Future Trends in Devices, Technology and Systems’’, 2008 453 Fig. 27.4 Nanobusiness spectrum ...... 454 Fig. 27.5 Modern vehicle with imbedded nanotechnology ...... 456 Fig. 27.6 Publications, patents, and public R&D funding share in Europe, the United Sates, and the rest of the world . . . 457 Fig. 28.1 Nanomedicine applications: diagnostics techniques to early target cancers ...... 462 Fig. 28.2 Benefits of nanotechnology ...... 463 Fig. 28.3 Risk assessment and management framework for nanotechnology ...... 465 Fig. IX.1 Important criteria for a successful development of nanoparticles and nanotechnology...... 468 Fig. IX.2 Main items that have to be investigated to understand the properties and risks of nanoparticles ...... 469 Fig. 29.1 Many sectors will be impacted by nanotechnology. Some of them are shown in the figure ...... 474 Fig. 29.2 Evolution of the number of commercial products based on nanotechnology between 2005 and 2010. Data from www.nanotechproject.org/inventories/ consumer/ ...... 475 Fig. 29.3 Share of the products based on nanotechnology, classified in categories as defined in www.nanotechproject.org/inventories/consumer/ ...... 475 Fig. 29.4 Categories and subcategories of market with commercial products based on nanotechnology. Figure built from the results of www.nanotechproject.org ...... 476 Figures xliii

Fig. 29.5 Different possible classification of nano-objects according to the ObervatoryNano project ...... 477 Fig. 29.6 Nanoworld twenty-first century: nanomaterials engineering base...... 478 Fig. 29.7 Families of nanomaterials according to the ObervatoryNano project ...... 478 Fig. 29.8 Some present or potential application of nanotechnology at home and for housing ...... 479 Fig. 29.9 Spectrum of nanotechnology applications in energy, environment electronics, and materials ...... 480 Fig. 29.10 Applications of nanoelectronics for technologies, spanning human health, society, and well-being ...... 481 Fig. 29.11 Three-way coupling among piezo-electricity, photo- excitation, and semiconductor with multiple potential applications ...... 482 Fig. 29.12 Areas of information and communications where nanotechnology can play a role ...... 482 Fig. 29.13 Fields in medicine where nanotechnology plays a role . . . 483 Fig. 29.14 Overview of nanobiotechnology branches ...... 484 Fig. 29.15 Areas where nanotechnology is involved in agriculture, food, and packaging domains...... 485 Fig. 29.16 Main areas where nanotechnology is important in the energy sector ...... 486 Fig. 29.17 Nanotechnologies enabling clean, safe, and efficient electric mobility ...... 487 Fig. 29.18 Important areas for environmental protection ...... 487 Fig. 29.19 Different threats in modern societies...... 489 Tables

Table 1 Units and subunits ...... viii Table 2.1 The number of transistors, the accuracy of the lithographic process, the area and transistor density are shown for different microprocessors which have been put on the market over the last two decades...... 27 Table 7.1 Evolution of the size of silicon wafers in microelectronics ...... 115 Table VII.1 Sectoral fuel share of different world energy consumption for the different energy sources for 2010...... 334

xlv About the Authors

Christian Ngô, ScD, was formely Executive General Manager of ECRIN (Echange et Coordi- nation Recherche-industrie) and Scientific Director of the Atomic Energy High Commission Office. In 2008, he founded EDMONIUM, a consulting company. He has worked in fundamental research for 20 years, and has published approximately 200 papers in the field. In the 1990’s, he moved to applied research and took three patents before holding several management positions such as advisor to the CEA’s CEO, Scientific Director of the Direction of Technology Research and so on. Dr. Ngô is author or co-author of 12 books (11 in French and one in English) and has contributed to several collective books. His main interest today in EDMO- NIUM relates to energy and nanotechnology.

Marcel Van de Voorde, Dr. ir.ing, Dr. h.c., 40 years experience in European Research Organisa- tions including CERN; European Commission research centres. Member of numerous Councils and Governing Boards of Research Institutions across Europe, the US and Japan. Emeritus Pro- fessorship at the University of Technology, Delft, The Netherlands, and a number of Visiting Pro- fessorships in Europe and worldwide. Member of the Science and Technology Ofﬁce of the French National Assembly/Senate in Paris, Executive Advisor to the IMEC CEO—President for Euro- pean Programmes in Belgium.

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